Update Licensing and Ocean Code

The code is the same released with the published paper M MAspero et al., 2017, Phys. Med. Biol. 62(3), http://dx.doi.org/10.1088/1361-6560/aa4fe7, the license has been updated and the link to Ocean Code has been added: https://codeocean.com/2017/10/28/mr-based-substitute-ct-generation-for-clinical-use-colon-quantification-of-confounding-factors/

Version published in the paper

Version linked to the paper "Quantification of confounding factors in MRI-based dose calculations as applied to prostate IMRT", Physics in Medicine & Biology, Volume 62, Number 3